Railway traffic-controlling apparatus.



PATENTED JUNE 5 O. J. COLEMAN. RAILWAY TRAFFIC CONTROLLING APPARATUS.

APPLIUATIOII FILED 1350.4, 1905.

T X WI [nae ntor:

UNITED STATES PATENT onrion.

CLYDE J. COLEMAN, OF NEW. YORK, N. Y. RAILWAY TRAFFIC-CONTROLLINGAPPARATUS.

Specification of Letters r atent. Application filed December 4.19 05."Serial No. 290.085.

Pa.tented June 5, i906.

. To all whom it may concern:

Be it known that I, CLYD J. COLEMAN, a citizen of the United States,residing in the borough of Manhattan, city of New York, in the county ofNew York and State of New York, have invented certain new and usefulImprovements in Railway Traffic-Controlling Apparatus, of which-thefollowing is a specification, reference'being had therein to drawing,forming a part the accompanying thereof.

My invention relates, broadly, to railway traffic-controlling apparatus,and that particular embodiment of my lnvention WhlOh I have particularlydescribed hereinafter and which is illustrated in the accompanyingdrawing belongs to that class of railway traffic-controlling apparatusknown as normal danger, home, and distant railway signaling apparatus w'ch 0 crates to control railway traflic on a railwayine b the display ofvisual signals, such as semap ore signals. a

Reliability of operation and simplicity and economy of construction andmaintenance are the broad obj ects of my invention.

It is a more specific object of my invention to provide means wherebytwo-different traffie-controlling apparatuses located. at differentpoints on a railway-line may be reliably and simultaneously controlledthrough one common trafiic controllin circuit extending from onetraffic-control 'ng apparatus to the other. To this end my inventioncomprises a traffic-controlling'circuit and means for supplying thecircuit with a composite electrlc current including a given currentcomponent distinguished by some current characteristics-such, forinstance, as a given periodic variationthe traffic-controlling circuitbeing arranged to extendjfrom one trafllc-con-- trolling, apparatuslocated. on the railwayline to another'trafiic-controllin apparatuslocated at a difierent point on t e railwayline and such circuitcontrolling both such traffic-controllingapparatuses, one .of suchtraffic-controllmg apparatuses being controllable by the given currentcomponent, distinguished in some instances, by a periodic variation, andthe other trafiic-controlling apparatus being controllable by anothercomponent of the composite current.

With regard to more specific details, 1t may be stated that it is anobject ofv my inventlon toprovi'de means wherebyone commoncontrolling-circuit-for instance, a rail-circuit including thetrafiic-rails of a railwaytrack-may be reliably employed simultaneouslyto govern a traffic-controlling or signaling ap aratus at the advanceend of the circuit su ject to control of a train in rear ofsuchapparatus and'to govern a traffic-controlling or signalin apparatusat the rear end of the circuit su ject to control -of a train in advanceof such apparatus. v In the illustrated embodiment of my .in-

vention the last-mentioned object is attained in a normal danger, home,and distant railway block-signaling system wherein the trafli'c-' railsof a given signaling-block are employed as conductors of a compositecurrent in the commoncontrollmg-circmt above mentioned,

the signaling a paratus at the advance end of the block being controlledor cleared by a current component havinga given periodic variation andsubject to presence of a-train in rear ofthe block, while at the sametime a the signaling apparatus at the. rearend of:

the'block is governed by another component of the same compositecurrentsubject'to control of a train in advance of such rear signal-* ing aparatus" and which may bein advance of the lock. j v

In my invention a given component of the composite currentwhich ischaracterized by' a given periodic variation may consist in an'alternatmg-current component, as in the specific instance illustrated,while another component'or'components of the composite}; current aredistinguished from the given? component by some. current characteristicblock or section through which the composite current flows, while thesourceof the current components which govern a traflic-controllingapparatus controllable by resence of trams in advance is located at t 0advance end of such railway block or section, and in this particularembodiment such current component governinga trafficcontrollingapparatus controllable from.in rear is a compo-- nent havingaperiodic varlatlon, while the components governing atraflic-controlling apparatus controllable by-a train in advance areunidirectional-current components.

' One particular object of myinvention is to 1 overn agiven'trafiic-controlling apparatus controllable by an electric currentcharacteriz'ed by aperiodic variation, an electric circuit in controlof'such apparatus and includ ing the traffic-rails of the railwayextending in rear thereof, means for supplying to thecontrolling-circuit an electric'current characterized by a periodicvariationsuch, for instance, as aperiodic alternation-and meanscontrolling such electric current by a roach of a train toward thetrafiiccontrdliing or signaling apparatus to actuate or control suchapparatus or moveit into unblocking or clear position. When thecontrolling-circuit is employed totransmitor is subjected to theinfluenceof some additional electric current or current component otherthan that emloyed to effect a given operation of the trafc controllingapparatus from a point in rear thereof,- my invention then broadlycomprehends a trafiic-controlling'or signaling apparatus located on arailway-lineand in a given i unblockin or clearing operation selectivelycontrollab e by a given current or current component, distinguished fromtheadditional current by r a given current characteristic whichmay-consist in a given periodic variation, and which givencurrentcomponent flows in an electric .circuiti-n control of thetraffic-controlling or signaling a paratus and extending in rear thereofalong t e line of traf fic, and means for controlling the given current.or current component from a point in rear of ,the apparatus to controlsuch apparatus.

In the illustrated embodiment of my invention thegiven current componentwhich effects control of the trafiic-controlling apparatus from a pointin rear is an alternating current, and 1n this particular embodiment thesource of such current is located at the rear end of thetraffic-controlling electric circuit, which location has some veryconsiderable advantages. Also in the illustrated-instance the additionalelectriccurrent or current componentnot employed to effect the givenoperation of the traffic-controlling or slgpallng apparatus'ls employedto efiect anot or operation thereof and is also employed to control asecond traffic-controlling or signaling apparatus at the rear end of thecontrolling-clrcuit. This use of the additional into clear positions.

current component, however, is only inci' dental to this particularembodiment of that signaling apparatus is effected from apoint ofcontrol in rear by selective responsiveness to some articular currentcomponent in lieu of or 1n discrimination against some other currentcomponent.

The accompanying drawing is a diagrammatic representation of a portionof a single railway-track equipped w1th a normal danger home and distantrailway block-signal- 7 ing system embodying my invention.

The diagram shows three successive rail-- way signaling ap aratuses A,B, and 0, located substantial at th e termini of successive signalinglooks or sections of the railway-line.

- The signaling apparatus is the same at each of the signaling-stationsA, B, and O, and a brief description of the'signaling apparatus A willtherefore be representative of the apparatus of the system generally.

Each signaling apparatus comprises home and distant signal semaphores,such as the semaphores 2% and 4 of the si aling apparatus A, mountedupon a suitab e si nal-post, such as 6*. (Indicated in dotted lines.)

The diagram shows separate signal-clearing motors 3 and 5, arranged toclear the home and distant signal semaphores, res ectively, the motorsbeing represented as though connected with the semaphore-blades bypull-cords adapted to move the blades It will of course be understoodthat this arran ement of signal- IOO semaphores and individua motors.isonly a diagrammatic representation intended to symbolize any meanswhatever whereby the respective signal-semaphores may be moved to clearpositions by passage of current in the local signal-clearing circuitswhich their respective diagrammatic motors are included and wherebyeither signal-semaphore may be returned to danger position by failure ofcurrent in its respective local signalclearing circuit.

The dia ram represents a ole-changing switch inc uding two contactevers9 and 10, combined with a distant-signal-kzircuitclosing-contact-lever11, the three contactlevers being mounted upon pivots arranged inalinement'and being connected by a common insulating-link 12*. Thiscombined ole-changingand distant-signalcircuit-closing switch isarranged to be actuated by movement of the home-signal semaphore 2",such arrangement being diagrammatically represented in the drawing by arod 7, de-

ending from a pivotal connection with the ome-signal semaphore and atits lower end carrying an insulated horizontally-extending foot 8,cooperating with two projections or fingers forming portions of thecontact-levers IIC 9* and 10, whichportions project from the 'pivotalcenters of such contact-levers opposite their pole-changing portions orfingers. The disposition of the foregoing parts is such that when thehome-signal semaphore reaches its clear position theole-changeractuating foot 8 will engage t e upper contact-lever 9 tothrow'the pole-changer into position for clearing the'distant signal ofthe signaling apparatus in rear, while at the same time throwing thecontact-lever 11 into position for partially closing the localclearingcircuit of the distant-signal semaphore 4.-

Each signaling apparatus comprises an alternating-current re ay, whichmay be constructed in any suitable manner, but which is represented inthe diagram as including a magnetic core, such as 17 surrounded by anenergizing-coil 24 and projecting upwardly through a conductive looporring 18, mounted upon the insulating-arm 19 of a pivoted lever,including also a contact -.finger 20 The insulating-arm andcontact-finger 19 and 20* extend horizontally from op osite sides of thepivotal center of the lever, t I e insulating-arm, with its conductivering, being considerably heavier than the contact-finger, so that suchinsulating-arm will always tend to fall and raise the contact-finger outof contact with its cooperating contact-stop 21. When an alternatlngcurrent is caused to circulate through the" energizing-coil 24, the core17 is sub'ected to an alternating magnetic flux, whic develops withinthe conductive ring 18 an alternating current circulat-v ing about theaxis of the core, but having a phase lag of more than ninety degreesbehind the inducing magnetic flux, whereby the mean reaction betweensuch flux and the induced current is rendered repulsive, so as to repelthe conductive ring 18 from the core 17*, thus raising theinsulating-arm 19 and depressing the contact-finger 20 into contact withits cooperating contact-stop 21.

Each signaling apparatus com rises also an advance clearing compound reay including opposed relay-magnets 25 and with contact-fingers 26 and28, controlled by an armature interposed between the magnets. Thisarmature is unbiased-that is to say, it has no normal bent toward eitherof the o posed magnets by gravity or by spring a ustment, but mere ymoves in the direction of pre onderating magnetic attraction exerted yeither relay-ma net. This armature is not shown, since t e constructionof such compound unbiased relays is well known in the signaling art. I

Each signahng apparatus also includes a home and distant clearing reartrack-relay,

such as the relay 3'2, controlling two contact-fingers 33 and 35'. Thecontact-finger 33 1s operated by a non-polarized armature, which isattracted by the relay when energized by current in either direction,and

' their positions an ger 35 is operated by a polarized armature which isactuated by the relay only when such relay'is energized with current ina given direction, which may be designated as the distant clearindirection, and such contact-finger 35 w en thus operated by itspolarizedv armature completes the local clearing-circuit of thedistant-signal-semaphore motor 5". Each signaling apparatus includesalso a rotary converter, diagrammatically represented as including adirect-current-motor armature 37 and an alternating-current-generatorarmature 38.

In describing the operation of the system represented inthe dlagram eachsignalingblock will be designated by the reference characters employedto designate the si naling a paratuses at the ends of the b ock. Thediagram-represents the various devices of the signaling a paratuses A,B, and C in 5 condition such as would be effected by resence of a train,as represented at T in t e block in rear of the signaling a paratus 'A,providing that the signaling-b ocks A Band B C- were both clear oftrains. In describing the sequence of actions of the signaling system aseffected by progressive movement of a train along therailwayline it maybe assumed that the train T, rep-' resented in the block in rear of thesignaling ap aratus A, has entered such block from 'a prehension of t eoperation of the system may not de end upon an understand ng of anyvoperatlon of the signaling apparatus which is not shown on the diagram,but which is located'at the rear end of the block I in rear of thesignaling apparatus A Before the train T enters the block in rear of thesignaling apparatus Athehome and the distant signal semaphores of thesignaling apparatus A, B, and O are all in danger ositions, and theshunt-coils, such as 30*, o the compound advance clearing-relayspreponderate over the series coils, such as 25, of such relays, so thatall the contacts, such as 26 27 and 28 29*,of such relays are open. Allthe alternating-current advance clearingrelays, such as 24", are alsonormally deenergized, and their contacts, such as 20 21, a

are therefore normally open. All the semahore-actuated pole-changers arenormally. in their positions effected b danger positions of thehome-signal semap ores, so that the pole-changing contacts, such as 9 13and 10 14*, are normally closed, while the semaphore-actuated contacts,such as 11 16*, included in the local clearing-circuits of thedistant-signal semaphores, are normally open.

' for negative pole of the advance trackattery &

i All therear hack-relays, such as 32, are normally energized by currenttransmitted in home clearing direction through the rail-circuits inadvance of such relays, so that the home clearing-contacts, such as 3334 of such relays are normally closed, while their distantclearing-contacts, such as 35 36, are normally n. p p

' Before t e train enters the block in rear of the signaling apparatus Athe series and shunt coils 25 and 30, respectively, of the compound"advance clearing-relay at the advance end of such block areenergizedthrough the followi circuit and circuit branches: inomone p0 eof the advancetrack-battery 22 of the signaling apparatus Afforinstance, the positive pole thereofthro h the conductor 47,semaphore-actuated p0 echanger contacts9 13, and conductor 43 tooneterminal of the shunt-coils 30 and also to the advance end'of thelett' rail L of the block, and from the conductor 43 thecircuit dividesin two branches, one branch leading through the coils of the shunt-relay30 to the conductor 44 and the other branch leading rearward through theleft rail L to the rear end of the block, and thence through the coilsof the rear track-relay at the rear end of the block to the right rail Rof the block, and thence forward through such right rail to theconductor 44, wherein the'two branches of the circuit reunite, andthence through such conductor 44, series coils of the advanceclearing-rela conductor 46, contacts'14 10, and con uctor 48 back to theo posite 22,--and until the train enters the block in rear of thesignaling apparatusA the relative ap ortionment of vresistances in theseries cm s 25, shunt-coils and rail-circuit branch in parallel with theshunt-coilsis such that the magnetic attraction of the shunt coils,considerabl preponderates over the magnetic attraction of the seriescoils upon their common unbiased armature, so that the contacts 26 27and 28 29 are open.

When under the foregoing conditions the train T enters the block 111rear of the signali apparatus A, the home and distant si na s at therear end of such block immediately assume d er positions, while thedistant-signalsemap ore at the rear end of the block-section in rear ofthe signaling apparatus A also assumes danger position, these movementsof the signals in rear of the train T being effected in a manner whichwill soon the series coils 25 might greatly reduce the amount of currentflowing through such shunt-coils, while at the same time atly increasingthe amount of current owing through the series coils 25 of such relay,since such series coils are-directly in series with the rail-circuitwherein the reduction of resistance is effected. Thereupon pre nderatein magnetic attraction upon the un liiased armature of the relay, so asto immediately close its contacts 26 27 and 28 29. Closure of thecontacts 26 .27 immediatel completes the local clearing-circuit of theome-signal semaphore 2, which local circuit isas follows: from one poleof the local battery 31 through the conductor 49, normally closedhomeclearing rear-track-relay contacts 33 34, conductor 54, contacts 2627, conductor 53, conductor 52, home-signal-clearing motor 3, andconductor 51 back to the opposite pole of the local battery 31.Immediately u on completion of the foregoing local home 0 earing-c1rcuitthe homesignal semaphore-2 commencesits-m-o vement to clear position. ap

Closure of the contacts '28 29 of the advance clearing-relay completesthe local circuit of the motor-armature 37 of the rotary converter, suchlocal circuit being as follows: from one pole of the local battery 31through the conductor 49, contacts 29 28, cohductor 50, motor-armature37, and conductor 51 back to the opposite pole of the local battery 31.Thereupon the rotary converter is immediately started and itsalternating-current-generator armature 38 commences to deliveralternating current to the signaling apparatus B through the followingcircuit: from one terminal or brushpf the alternatingcurrent-generatorarmatii the conductor 42, condenser 39 conductor 40,

left rail L of the block A B, conductor 43, condenser23,-conductor 45coil 24" of the alternating-current advance clearin -relay, conductor44, right rail R rearwar to the conductor 41, and thence through suchconductor to the opposite brush or terminal of thealteinating-current-generator armature 38 It will be noted that thealternatingcurrent advance clearing-relay 24 is included in the foreoing circuit by being bridged R in series with the condenser 23, whichis of'such capacity as to freel admit alternating current through the reay 24, while at the same time such condenser effectually prevents flowof unidirectional current from the advance track-battery 22 through thealternating-current relay 24, thereb avoiding any waste ofbattery-current w 'ch might occur if'such current were free to flowthrough the v. alternating current relay. The condenser 39, likewise inseries with the alternating-current-generat-or armature 38, bridgedacross the rails L R at the rear end of the IOO " across the a vanceends of the track-rails L preventing wasteful flow of battery currentCurrent through the generator-armature. in the foregoing rail-circuit ofthe block A B energizes 1ts alternating current advance clearing-relay24?, so as to close the contacts 20 21 thereof, and thus'complete thelocal clearing -'-circuit of the homesignal semahore 2*, such localclearing-circuit being as ollows: from one pole of the local battery 31through the conductor 49*, home clearing-coht-ac ts 33 34 closed bycurrent flowing in home clearing direction through the rear track-relay32 and from the contact 34 through the conductor 54', contacts 21 20conductor 52*, home-signal clearing-motor 3 and conductor 51 back to theopposite pole of the local battery 31*. Such current throughthe motor 3?operates the motor to clear the home-signal semaphore 2 which when itreaches clear osition reverses its semaphore-actuated po e-changer,while at the same time closin 1ts semaphore-actuated contacts 11 16*,inc uded in the local clearing-circuit for the distant-signal semaphore4". As the semaphore-actuated pole-changer of the signaling-a paratus Bis reversed the circuit of the a vance track-battery 22 through the reartrack-relay 32 at the rear end of the block A B is of course momentarilybroken, so that such rear track-relay 32 is momentarily denergized andmomentarily opens its contacts 33 34, thus momentarily opening the localclearing-circuit of the home slgnal 2*; but by the employment of aslowacting semap hore-retaimng clutch or other means well known to theart the home-signal semaphore 2 is retained in its clear position duringthe momentary break in its local clearing-circuit, such local home"clearing-circuit bemg immediately reclosed at its contacts 33 34 byrenergizationiof the rear trackrelay 32 by current transmitted indistant clearing dlrectlon from the advance trackbattery 22 as soon asthe semaphore-actuated pole-changer of the signaling apparatus B reachesits-reversed position.

As soon as current in the distant clearing I direction is established intherail-circuit of l the conductor 49, contacts 33 34", conductor 54contacts 26" 27, conductor 53", conductor 52, semaphore-actuatedcontacts 11 16, already closed by clearing of the homesignal semaphore2", and from the contact 16 through the conductor 55,distant-signalclearing motor 5, conductor 56, contacts 36 35, andconductor 51 back to the opposite pole of the local battery 31. Currentin the foregoing local distant signal clearing 4 aratus A and enters athe rear end of the block A B, thereby immediately short-circuiting therails L R of such block, so as to cut oil? the transmission ofclearing-current from thetrack-battery 22 at the advance end' of theblock rearward to the rear track-relay 32 of the si naling apparatus A'.Thus such. rear tracli-rela is immediately deenergized and immediate yo. ens both its home clearing and its distant c earing contacts, so asto open the local-home clearing and distant clearing local circuits andcause the home and distant signals 2 and 4 'to assume danger positions.The short-circuiting effect of the train in the block A B. alsoimmediately cuts off the transmission of alternatin generator-armature38 0 the signaling apcurrent from the paratus A forward throu h therail-circuit of the block to the alternating-current advanceclearing-relay 24 of the signahng apparatus '13, whereupon suchalternating-current. relay immediately 0 ens its contacts 20 21, so asto momentari y open the local clearing-cir- A the compoundclearing-relay of the signaling apparatus A. Such pre onderance of theseries coils 25 over the s unt-coils 3O also simultaneously closes thecontacts 28 29 to v completethe local circuit" ofthe motor-armature 37 bof the rotar converter of the block B C, so as to imme iately commencetransmission of alternating clearing-current forward through such blockto the alternatingcurrent advance clearing-relay 24 of the signalingapparatus 0. Such current in the clearing-rela 24; effects clearing ofthe homesignal semap ore 2, so as to reverse its s'ema-,

hore-actuated pole-changer and establish distant clearing-current in theblock B C to clear the distant-signal semaphore 4' at the rear endthereof all in the manner hereinbefore set forth with regard to thecorresponding clearing operations of the home-signal semaphore 2 and thedistant-5i a1 sema hore 4". The train then procee s into the hlock B C,causing the home anddistant signals 2 and 4* at the rear end thereof toassume danger positions and clearing the homesignal in advance of thesignali C, so as to clearthe distant signa 4 0i such apparatus. Thus thetrain proceeds along apparatus in advance thereof.

It will be noted that when a train has entered a given signaling-block;so as to estab lish alternating-clearing current iii the block next inadvance thereof, the rail-circuit of such block next in advance is enplied with a composite electric current, which in the present instancecomprises one unidirectional uniform current component delivered by theadvance-track battery, while the other component is characterized byaperiodic variatlon and is in the present instance an alternating-currentcomponent delivered by the.

generator-armature at the rear end (if the rail-circuit. The reartrack-relays are selectively responsive to the unidirectional uniformcurrent componentthat is to say,

' they respond to-this current component and do not respond to thecurrent component characterized by a periodic variation. Also the"alternating current advance clearing relays are-selectively responsiveto the current component, having a periodic variation in lieu of acurrent component of uniform value.

In designating a uniform or unidirectional current or current componentthese terms are employed to describe character or condition of a currentor current component during any given moment or interval and incontradistinction to a current component which is characterized by aregular or rythmic periodic variation or alternation-that is to say,

the terms are employed to designate a cur' rent or currentcomponentwhich is unidirectional or substantially uniformfduringits em-'ployment to maintain some given conditlon of the traffic controlling orsignaling appa- Y ratus which it covers. It is to be understood,

however, that these terms do not preclude the employment of aweakuniform current to perform a given operation, such as clearing ahome signal, and the subsequent movement of astrongeruniform current toperform another operation, such as clearing a distant signal; nor dothese terms preclude the employment of unidirectional current of onepolarity to perform one of such operations and the subsequent emplo mentof another unidirectional current of t e opposite polarity to erform thesecond of such operations. I In suc cases the current of lesser strengthfor performing one operation, the current of greater strength employedto perform another operation, the current of one polarity to'perform oneoperation, and the current of i ceases -opposite polarity performing asubsequent operation are each substantially uniform and unidirectionalwithin the meaning of these termsas employed by me In the illustratedembodiment of my invention two substantially uniform currents areemployed successively to clear the home and thedistant signals of agiven signaling apparatus, each current being substantially uniform andunidirectional, so long as it is maintained, but the secondcurrenthaving a polarity different from the first current.

-It is apparent that my invention may be particularly described, allsuch other embodi- I railway traffic-controlling apparatus located at agiven point on the railway-line and controllable by thecontrolling-circuit and by itscurrent component having the givenperiodic variation, and another electrically-controllable railwaytraffic-controlling a paratus located at a point on the railwa inedistant from the first-mentioned tra 'c-controlling apparatus andlikewise arranged in controllable relation to the, controlling-circuitbut controllable by another component of its composite current. I

2. A railway block signaling system comprisinga signaling-circuitincluding the traffic rails of a block or section of the railwayline,means for supplying the signaling-circuit with a composite electriccurrent including a current component having a given periodic variation,an electrically-controllable signaling apparatus located at one end ofthe railway-block and controllable by the signaling-circuit and by itscurrent component having the given periodic variation, and a secondelectrically-control]able signaling a paratus located at the other endof the blocli also in controllable relation to the signaling-circuit butcontrollable by another component of its composite electric current.

3. A railway traffic-controlling system comprising an electrictraffic-controlling circuit extending along the line of traffic of arailwa a source of electric current characterize by a given periodicvariation located at a given point on the railway-line and ar ranged tosupply such current to the controlling-circuit, a second source ofelectric cur- IIO rent having a characteristic different from v thegiven periodic variation and arranged to supply such different currentto the trafficcontrolling circuit but located at a point on therailway-line distant from the first-mew. tloned source of current, atrafficcontrolling ,apparatus located at a point on the railwaylinedistant from the first-mentioned source of current and controllable bythe controllingcircuit and by the current of given periodic variationtransmitted through the control llng-circuit in a given direction alongthe railway-line from such first-mentioned source, and a secondtraflic-controlling apparatus cated on the railway-line at a pointdistant from the second source of current and controllable by thecontrollingcircuit and by the current transmitted from such secondsource way-line, a source of" electric current characterized by a givenperiodic variation located substantially at one end of the section andarranged tosupply such current to the rail- CiICIlllJ, a signalingapparatus located substantially atthe other end of the section andcontrollable by the rail-circuit and by the current of given periodicvariation, a second source of electric current different from thecurrent of given periodic variation and located substantially at theopposite end of the section and arranged to supply such difl erentcurrent to the rial-circuit, and a second signaling a paratus locatedsubstantially at the end of t e sectionopposite the second source ofcurrent and controllable by the rail-circuit and by the current fromsuch second source.

5. A railway traflic-controlling, system comprising an electrically-controllable trafiiccontrolling apparatus located at a givenpoint on a railway-line and normally in-condition to revent trains fromproceeding along such rai way-line in advance of such given point andcontrollable b a controlling electric current characterize by a periodicvariation, a twine-controlling rail-circuit including traffic-rails ofthe railway extending in rear of the traflic-controlling apparatus andarranged in control of such apparatus, means for supplying to therail-circuit an electric current characterized by a periodic variation,and means for controlling such current of periodic variation from acontrolling-point in rear of the traffic-controlling apparatus to changesuch apparatus from its aforementioned normal condition.

6. A railway traffic controlling system comprising anelectrically-controllable trafliccontrolling apparatus located at agivenpoint on a railway-line and normally in condition to prevent trainsfrom proceedlng along such railway-line in advance of such given ,triccurrent characterized by a point and controllable by acontrollingelectric current characterized by a periodic variation, atraffic-controlling rai -circuit including traffic-rails of the railwayextending in rear of the traffic-controlling apparatus and arranged incontrol of such apparatus,

means for supplyingto the rail-circuit an electric current characterizedby a periodic va- 7 nation, and means for controlling such current ofperiodic variation automatically by approac of a train toward thetrafiic-controlling apparatus from a point in rear thereof to'changesuch apparatus from its afore-' mentioned normal condition.

7. A railway traflic controlling system comprising ane1ectrically-controllable traflie-controlling apparatus located at agiven point on acrallway-line and normally in condition to preventtrains from proceeding along such railway-line in advance of such givenpoint and 'controllableby a controlling eleceriodic va riation, atraffic-controlling rai -circuit ineluding traffic-rails of the railwayextending in rear of the traflic-controlling apparatus and arranged incontrol of such apparatus, a source of electric current characterized bya periodic variation located at the rear end of the rail-circuit andarranged to supply such current to such circuit, and meansfor'controlling such current of periodic variation from acontrolling-point in rear of the trafficcontrolling'apparatus to changesuch apparatus from its aforementioned normal condition. I r

8. A railway trafiiccontrolling system com-prisin anelectrically-control]able traffic-control ing apparatus located at agiven point on a railway-line and normally in condition to preventtrains from proceedin along such railway-linein advanceof sue givenpoint and controllable bya controlllng electric current characterized bya perlod c variation, a traffic-controlling rail-circuitincluding'traflic-rails of the railway extending in rear of thetraffic-controlling apparatus and arranged in control of such apparatus,a source of electric currentcharacterlzed by a periodic variationlocated at the rear end oi the rail-circuit and arranged to suplysuch'current to such circuit, and means or controlling such current ofperiodic variation automatically by approach of a train toward the traflic-control ing apparatus from a point in rear thereof to change suchapparatus from its aforementioned normal GOIldltion.

9. A railway signaling system comprisin a normal danger-signalingapparatus locate at a given point on the railway-line and controllableby an electric current characterized by a periodic variation, acontrolling ra1l-c1rcuit in control of the signaling apparatus andincluding traflic-rails of the rai ing in rear of the signalingapparatus, means way extendfor suppl to the rail circuit -a fcurrentcharacterlze by a periodic var atlon, and

means for controlling such current froma point in rear of the signalingapparatus in order to produce a clear indication of such apparatus. v

10. A'railway signaling system comprising a normal danger-signalingapparatus located at a given point on the railway-line and-com,trollable by an electric current characterlzed by a periodic variation,a controlling rail-circuitlin control of the signaling apparatus andincluding trafiic-rails of the railway extending in rear of the si alingapparatus, means including trafiic-rails of the rai way extending rearof the signaling apparatus, a source of electric currentcharacterlted bya periodic variation located substantlally at the rear end of therail-circuit and arranged to supply such current. to such circuit, and

means for controllingsuch current firbm a point infirear of thesignaling apparatusin order to produce a clear indlcatlon of suchapparatus. I

'12,. A railway traffic-controlling system comprisin anelectrically-controllable traffic-control' g apparatus located on arailway-line, and normally in'condition. to prevent continuance oftrains along such railway-line and controllable by an electric-currentcomponent having a distinguishing characteristic, means for sup 1trolling rearward a ong the railwaydine and'arra *to conduct the currentcomponent having 7 an electric-current component having t e distinguishin'g characteristic, a trafiic controlling electric circuit incontrol of the traflic conapparatus and extending therefrorn .thed-istinguishing characteristic but also I ling the current componenthaving the dis-' 5S I iven clearing operationof thetraflic-controlsubjected .to another current com onent different incharacter, and means or controltinguishing characteristic whereby toeffect a ng apparatus such traffic-controlling apparatus beingselectively controllable by such 69, to the other different current:component to current component to perform such given clearmg; operationand being not responsive perform such given 0 oration.

13. A railway tra -ccontrolling system eor nprising anelectrically-controllable railway traffic-controlling apparatus locatedon eeamos a railway-line and normally blocking traflic on suchrailway-line, means for supplying an electric-current componentcharacterized by a given periodic variation, a traffic-controL' lingelectric circuit in control-of the trafficcontrolling apparatus andextending therefrom rearward along the line of railway traffic andarranged to conduct the current comonent haying the given periodicvariation ut also subjected to the flow'of'another different currentcomponent, and means for controlling the current having the givenperiodic variation from a point in rear of. the traffic-controllilapparatus to control such traffic-controlling apparatus, suchtrafiiccontrolling apparatus being selectively responsive to suchcurrent having the given periodic variation toperform a given clearingtraffic-controlling operation but being not thus responsive to theo'therdiflerent'curr rent component.

14.- A railway trafiic controlling system comprising an-electrically-controllable railwa traffic-controlling apparatus locatedon a rai way-line and norma y blocking traffic-on such railway-line,means for supplyi'n an electric-current. component characterizet l b agiven periodic variation, a traffic-contro lin electric circuit incontrolofthe trafiic contro ling apparatus and extending therefromrearward a ong the line of railway trafiic and arranged to conduct thecurrent component having the given eriod-ic variation but also subjectedto the ow of a uniform current component, and means for controlling thecurrent shaving the given periodic variation from a point in rear of thetrafiic controlling apparatus to control such traffic-controllingapparatus, such traflic controlling alpparatus being selectivelycontrollable by suc current having, the givenperiodic variation toperform a given clearing traffic-controlling operation butr.being'notthus responsive to the uniform current component.

15. A railway traflic-controllirig system comprisin an electricallycontrollable traffic-control ing ap aratus located on a railwayline andnormal y blocking traffic on such railway-line, means for supplying anelectriccurrent' component characterized by a eriodic variation, arail-circuit in control 0? the traffic-controlling a paratus andincluding the traffic-rails of t e railway extending in rearthereof'andarranged to conduct the current component having the periodic ,varia-,t1o n but also subriected to flow of anon-peri- OdIC eurrent, -an meansfor controlling the current component havin the periodic variation by aproach of a train toward the traffic-oontrol ing apparatus from inrearthereof whereby to control such traificmontrolling apparatus, suchapparatus being selectively res onsive to. the current componentcharacterized by the perlodic variation and controllable thereby toperform a given clearing oporig eration and being not controllable bythe noncomprising a traflic-controlling electric cirperiodic current toperform such operation;

16. A railway traffic -controllin system comprising an electricallycontrollab e trafliccontrolling ap aratus located on a railway line andnorlna ly blockin traffic on such T8114 way-line, means for su p ying analternating electric current, a tra c-controlling rail-circuit arrangedin controlof the traffic-controlling apparatus and including thetraflic-rails of the railway-line extending in rear thereof andcommunicating with the source of alter nating current but subjected alsoto a non-flue:

tuating electric current, and means for controlling thealternating-current component in the rail-circuit from a'fpoint in rearof the traffic-controlling apparatus to control such apparatus, suchapparatus being controllable by such alternatlng-current component toerform a given clearing operation and not eingl controllable to perform'suchoperation by t e non-fluctuating current component in therail-circuit. a l

' 17. Arailwa signaling system comprising,

a si al-contro ling rail-circuit including the a source of electriccurrent characterized by a given perio dicvariation locatedsubstantially at the rear end of the section and arranged to supply suchcurrent to the rail-circuit, a second source of electric current havinga characteristic different from the given perio dic varilocated'at theother ation and located substantially. at the 'advance end of thesection and arranged to su ply such different current to therail-circuit, a signaling apparatus located substantially at the advanceend ofthe section and controllable by the rail-circuit and by itscurrent havin the ivenperiodic variation, and a secon si' na ingapparatus located substantially at t e rear encl of the section and'controllable by the rail-circuit and by the difier- --'ent currentdelivered by the secondsource of current;

18L A I railway traflic controlling system comprisir, atraflic-controlling electric cir cuitextendmg between two points on theline of traflic of a railway, means for supplying thetraffic-controlling circuit with a composite electric current includinga component having a periodic variation and a substantially uniformcomponent, a railway traffic-controlling ap aratus located at one of thetwo points on t e line of trafiic and controllable y thetraflic-controlling circuit and by its current component having theperiodic variation, a second traffic-controlling apparatus oint on theline'of trafiic and also contro'lable' by the trafiiccontrolling circuitbut by its-substantially uniform current component, and means forcontrolling the components of the composite current to control thetrafli -controlling appa ratuses.

ing a signal-control 19. Airailway traflic-controlling system cuitextending from a given point'on a railway-line to a second point distantfrom the given point, a source of electric current havmg a periodicvariation located at the given point on the railway-line and arrangedto. suppl such current to the controlling-circuit, a tra -c-controllingapparatus located at the second point and controllable by thecontrolling-circuit and by the current of periodic variation, a sourceof substantially un form electric current located at such second pointon the railway-line and arranged to supply such substantially uniformcurrent to the controlling-circuit, another traffic-controlling aparatus located at the given point on the ram way-line and controllableby the con trolling-circuit and by its substantially uniform currentcomponent, and means for controlling the component having a periodicvariation and the substantially uniform component,to control thetraffic-controlling apparatuses.

20. A railway signaling system comprisin a signal controllingrail-circuit includingtra fic-rails of a section of the railway, asource of signal-controlling electric current characterized by aperiodic variation located sub- 'stantiallyat one end of therailway-section and arranged to deliver its current to therail: circuit,a signaling apparatus located substantially-at theopposite end'of thesection and controllableby the-rail-circuit and by the current orperiodic variation, a source of substantially uniform signal-controllingcurrentlocat'ed'substantially at such opposite end of thesection andarranged to -deliver its current to the rail-circuit, a second railwaysi naling'apparatus located substantially at t e first-mentioned end ofthe section and controllable by the rail-circuit and by itssubstantially uniform current component, and means for controlling thecurrent component" characterized by a periodic variation and thesubstantially uniform current component, to tus es. -e v 21. A railwaysignaling system compris- 'ng rail-circuit including traffic-rails of a,section of the railway, a source of substantially uniform signalingcurrent communicatin with the rail-circuit substantially at the a vanceend of the section, a signaling ap aratus at the rear end of the sectioncontro lable by the rail-circuit and by its substantially uniformsignaling-current component, a source of signaling-current having a,periodic variation communicating control the signaling apparaforcontrolling such current component of periodic variation from apoint inrear-of the section.

22. A railway signaling system comprising a signal-controllingrail-circuit including traffic-rails of a section of the railway, asource of substantially uniform signaling-current communicating with therail-circuit substantially at the advance end ofthesection, a Signalingapparatus at the rear end of the section controllable by therail-circuit and by its substantially uniform signaling-currentcomponent, a: source of signaling-current having a periodic variationcommunicating with the rail-circuit fat .the rear end of the section, asignaling apparatus at the advance 'end of the section controllable bythe railcircuit and by its signaling-current component having a periodicvariation, means for controlling such current component of periodicvariation from a point in rear of the section, and means forcontrollingthe substantially uniform signaling-current component from a oint inadvance of the section.

23'. normal danger railway block-signaling systemcomprism a signalingrail-circuit including the trafllc-rails of a signalingblockpf therailway, a source of substantially uniform electric current arranged tosupply a substantially uniform current component to the rail-circuit atthe advance end of the block, a signaling a paratus .at the rear end ofthe block control able by the railcircuit'a'nd by itsuniform currentcomponent, a'source of electric current characterized by'aperiodicvariation arranged to supply sucha current component to'tlie rail-.'circuit at the rear end of the block, a si nalcomponent to therail-circuit at the advance end of the block, a source ofanothersignalcontrolling current component characterized by a periodicvariation arranged to supply such current com onent to the rail-circuitat the rear end 0 the block, a signaling apparatus at the end of theblock controllable by the rail-circuit and controllable by selectiveresponsiveness to its current. component of periodic variation toperform one operation and controllable to perform another op-' erationby responsivenessto the substanceases tially uniform current component,a second signaling ap aratus at the rear end of the block contro lableby the rail-circuit and by its uniform current component, a secondsignal-controlling circuit including traffi 'c-rails of the railwayextendin in rear of the block and arranged to contro the currentcomponent of periodic variation in the first-men-' tioned rail-circuitto effect the first-mentioned operation of the first-mentionedsignalingapparatus at the advance end of the block, the substantiallyuniform current component being controllable by presence of a train inthe block to effect the second-mentioned operation of suchfirst-mentioned signaling apparatus.

25. A normal danger home and distant railway block-signalin systemcomprising al-controlling 1 rai circuits extending through the various.si aling-blocks and including the traffic-rai s thereof, means for suplying to the rail-circuits a signal-control ing current characterized bya periodic variation, signaling apparatuses located at the termini ofadjacent blocks, and each including a home-signal controllable by thesignal-controlling rail-circuit of the block next in advance and eachsignaling a paratus including also a distant signal, for cat: distantsignal a controlling-circuit controllable by the rail-circuit of theblock second in advance when laced in controllable-relation to suchsecon advance rail-circuit, each signaling apparatus being responsive tothe current component of periodic variation in the signalcontrollingcircuit. extendin through the block next in rear to place t econtrollingcircuitof the next reardistant 5i al in controllable relationto the next ariv ance' railcircuit', and each signaling ap aratus beingalso controllable by presence 0 a train in the next rearblock to controlthe current of pe-' riodic varieitioninthe next'advance block and thusoperate the next advance signaling apparatus to place its first advancerail-circuit in control of the distant signal next in rear of suchlast-mentioned signaling apparatus. 26. A normal danger home and distantrailway block-signaling system comprising signal-controllingrail-circuits including the trafficqails of the various signaling-blocksof the railway, and home and distant railwaysignaling apparatuses at thetermini of successive blocks each including a source ofsignal-controlling'current having a periodic variation arranged tosupply the rail-circuit in advance, a source of non-periodicsignal-controlling current arranged to supply the rail circuit in rear,home-si al clearmg means controllable jointl by ti: non-periodic currentcomponent 0 the rail-circuit in advance and by signal-controllingcurrent in. the next rear rail-circuit, means jointly controllable bysuch non-periodic current component of the next advance rail-circuit andby the Mm I30 rent component of periodic variation the next rearrail-circuit .to effect a distant-signalclearing variation in thenon-periodlc current component of such next rear distant signal, andmeans for clearing the local" distant signal controllable by thenon-periodic cur-' rent com onent of the next rear rail-circuit tocontro the current com onent of eriodic variation in the next a yancerai -circuit and thus operate the next advance si naling apparatus toefiect the distant-signa -clearc railway block-signalin arranged tosupply signal-controlling current to the rail-circuit of the next rearblock, homesignal-clearing means controllable jointly b thebattery-current in the next advancerai circuit and by one component ofthe "signaling-current in the next rear rail-circuit, current-reversingmeans controllable jointly by such a battery-current of the next advancerail-circuit and by the alternating current component of the next rearrail-circuit and arranged to reverse the battery-current in such nextrear rail-circuit, local distant-signal-clearing means responsive toreversal of battery-current in the next advance rail-circuit, andcurrent-controlling means controllable by the battery-current 1n therail-circuit of the next rear block and re s'ponsive to presence of atrain therein to establish flow of alternating current from the sourcethereof through the next advance rail-circuit to op erate thenext'advance signaling apparatus to reverse the battery-current in suchnext ad-' vance rail-circuit and clear the local distant signalat therear end thereof.

r 28. A railway traffic-controlling system comprising atraffic-controlling electric circuit. extending from a given point on arail way-line to alsecond point on therailwayline distant from the givenpoint, means for supplying the traffic-controlling electric circuit witha composite electric current including difierently characterized currentcomponents, a traffic-controlling apparatus at the first-mentionedpointcontrollable by the traffic-controlling electric circuit and by onecomponent of its composite current, a second traffic-controllingapparatus located at the distant point and also controllable by thetraflic-controlling circuit but controllable by another component of itscomposite curparatuses.

rent, and means for controlling the components of the com ositetraffic-controlling current to control t etrafiic-controlling apv v 29.A railway traffic-controlling system comprising a traific-controllingelectrlc circuit extending from one point ona railwayline to a secondpoint on the railway-line distant from the first point, a source ofoneelectric current component located at the first point and arranged tosupply such current component to the trafiic-controllin circuit, asource of a current component 0 different character located at thesecond point andrarranged to supply such difierent current component tothe traffic-controlling circuit, a traffic-controllin apparatus locatedat the second point an controllable by the traificcontrolling electriccircuit and by the current component delivered by the source ofourtrolling apparatus located at such first point rent at the firstpoint, another trafiic-conand controllable by the traific-controllingcircuit and by the current component delivered by the source of currentat the second point, and means for controlling the components of thecomposite current to control the traflic controlling apparatuses.

30. A railway traffic-controlling system comprising an electrictraffic-controlling railcircuitincluding the traffic-rails of a sectionof the railway, means for supplying to the rail: circuit a compositeelectric traffic-controlling current includin the components ofdifferent character, a tra 'c-controlling apparatus located at one endof the section and controllable by the rail-circuit and by one componentof its composite current, a second traf fic-controlling apparatuslocated at the o posite end of the section and also control able by thetraffic-controlling circuit but by a difierent component of itscompositecurrent, and means for controlling the components of thecomposite current to control the trafficcontrolling apparatuses.

cdmprising a source of electric current'located at one point on arailway-line and arranged to supply its current to the trafficrailsthereof, a second source of electriccur-.

rent of different character located at a second point on the railwaydistant fromthe first point but likewise arranged to supply its currentto the traflic-rails, an I electricallycontrollable traific controllingapparatus located on the railway-line at a pointdistant in one directionfrom the first-mentioned source 11 0 31. A in way traffic-controllingsystem.

of current and electrically controllable by the traffic-rails and by thecurrent com onent from such first source transmitted t roughally-controllable trafliccontrolling a paratus located at a point on therailway istant in the opposite direction from the second source ofcurrent and electrically controllable I such rails in such direction, asecond electricby the trafiic-rails and by the current compo-- nent ofdifferent character transmitted from such second source in such oppositedirection through the traffic-rails and to the second railway, a sourceof traflic-controlling elec- .rent component transmitted from the sourcetric current arranged to su ply such current to therail-circnit at the avance end of the section, a traflic-controlling apparatus located at therearend of the section and controlla'ble by the rail-circuitjand by itsourof current at the advance end of the section, a second sourceof'electric current different in character from the current of thefirstmentioned source and arranged to supply such difi'erent current tothe rail-circuit at the rear end of the section, a second traffic- Icontrolling apparatus located at the advance end of the block andcontrollable by the railcircuit and by the second difierent currentcomponent transmitted from the second source of current at the rear endof the section, and means for controllingthe second current componentfrom a point on the railway-line in rear of thesection.

33. A normal danger home and distant railway block-signaling systemcomprising si naling rail-circuits includin the trafiic-ra' s of thevarious signaling-bloc of the system, and electrically-controllable homeand distant railway signaling apparatuses located at the termini ofsuccessive si naling-blocks and each including a source o sinaling-current of'definite character arran e 'to supply the rail-circuitofthe next bloc in rear, a second sourceof signaling-current of secondor difierent character arranged to supply the railcircuit of the blocknext inadvance, home'- signal-clea'ring means controllable jointly bythe signaling-currentcom onent of first or definite charactertransnntted through the next advance rail-circuit and by onesignaling-current component of the next rear railcircuit, means jointlycontrollable by such current component of first character in the nextadvance rail-circuit and by the second or difierent current component inthe next rearrail-circuit and arranged to'efiect adistant-signal-clearmg change in the current component of firstcharacter in the next rear rail-circuit,-and localdistant-signal-clearmeans controllable by the current compo-. nent offirst character in the next rear railcircuit to control the currentcomponent of second character in the next-advance rail-circuit and thusoperate the next advance si naling a paratus to effect thedistant-signal-c earing c e in the current'of first character in clearthe distant signal at the rear end thereo 34. A railwaytrafiic-controlling system comprisinga trafiic-controlling electriccircuit, means for supplying the controlling-oi} cuit with a compositeelectric current including a current component havin a given periodicalternation, an electrical y-controllable railway traflic-controllingapparatus located at a given point on the railway-line and controllableby the controlling-circuit and by its current component having the givenperiodic alternation, and another e ectricallycontrollable railwaytraffic-controlling apparatus located at a point on theirailway-linedistant from the first-mentioned traffic-contro apparatus and likewisearranged in co'ntro lable relation vto the controlling-circuit butcontrollable by another component of its composite current.--

35. A railway block-signaling system comprisin a signaling-circuitincluding the traffic-rai s of a block or section of the railwayline,means for supplying the signaling-circuit'with a'com po'site electriccurrent including a currentcomponent having a given riodic alternation,an electrically-control able signaling apparatus located at one end ofthe railway-block and controllable by the signal ing-circuit and by itscurrent component havin the given periodic alternation, anda seconelectrically-controllable signaling ap' pa'ratus located at the otherend of the block also in controllable relation to the signaling-circuitbut controllable by another component of its composite electric current.

36. A railway signaling system comprising a signal-controlling, electricrail-circuit including the trafiic-rails of a section of therailway-line, a source of electric current characterized by a ivenperiodic alternation located substantially at one end of the section andarranged to sup ly such current to the rail-circuit, a signa ingapparatus located substantially at the other end of the section andcontrollable by the rail-circuit and by the current of given periodicalternation, a second source of electric current different from thecurrent of given periodic alposite end of the section and arranged tosupply such diiferent current to the rail-circuit, and a secondsignaling apparatus located substantially at the end of the sectionopposite ternation and located substantially at the opnating current ofelectricity, a traflicvcdntrolling rail-circuit including trailic-railsof the railway extending in rear of the trafficcontrolling apparatus andarranged in control of such apparatus, means for supplying to therail-circuit an alternating electric curfic-control ing apparatuslocated at a given point on a railway-line and normally in condition toprevent continuance of railwaytrains along a given track beyond suchgiven point and controllable by a controlling alternating current ofelectricity, a traffic-controlling rail-circuit including trafiic-railsof the railway extending in rear of the trafficcontrolling apparatus andarranged -in-'con trolof such apparatus, means for supplying to therail-circuit .an alternating electric cur rent, and means forcontrolling such current automatically by approach of a traintoward thetraflic-controlling apparatus from a point I in rear thereof toreversethe aforementioned normal condition of such apparatus.

39. A railway traific controlling system comprising anelectrically-controllable traffic-controlling apparatus located at agiven point on a railway-line and normally in conv dition to preventcontinuance of railwaytrains along a given track beyond such'glven pointand controllable by a c'ontrolling electric alternatin current, atrafiic-controlling rail-circuit inc uding trafiic-rails of the railwayextending in rear of the traffic-controlapparatus and arranged incontrol of apparatus, a source 0 electric alternating current located atthe rear end of the rail-circuit and arranged to suppl such current tosuch circuit, and means or controlling such alternating current from acontrolling-point in rear of the traffic-controlling apparatus toreverse the aforementioned normal condition ofsuch apparatus.

A0. A railway signaling system comprising a normal danger-signalinapparatus lo-' cated at a iven point on the railway-line and controlable by an electric alternatin current, a controlling rail-circuit incontro of the signaling apparatus and including traf-' fic-rails ofthe-rai way extending in rear of the signaling apparatus,means forsupplyin to the rail-circuit an alternating current, an means forcontrolling such current from a point in rear of the signaling apparatusto clear the si al.. 1

41. A rai way signaling system-comprisin a normal danger-signalingapparatus locate at a given point on the railway-line and controllableby an alternating electric current, a controlling rail-circuit incontrol of the signaling ap aratus and including trafiic-rails of therai way extending in rear of the signaling apparatus, means forsupplying an alternating current to the rail-circuit, and

means forl controlling such current automatically by approach of atraintoward the signaling apparatus from in rear to clear the signal. I

42. -A railway signaling system comprisin a normal danger-signalingapparatus locate at a given point on the railwayline and controllable byan electric alternating current, a controlling rail-circuit'in controlof the si naling apparatus and including traflic-rai s of the railwayextending in rear of the signaling apparatus, a source of alternatingelectric current located substantially at the rear end of therail-circuit and arranged to supply such current to such circuit, andmeans for controlling such current from .a point in rear of'thesignaling apparatus in order to clear the signa v 43. A railwaytraffic-controlling system comprisin an electrically-controllabletraffic-control ing apparatus located on a railway-line, means forsupplying an electric current component having a distinguishmgcharacteristic, a traffic-controlling electric circuit in control of thetraffic-controlling ap paratus and extending the'refroni rearward alongthe railway-line and arranged to conduct the current com onent havingthe distinguishing characteristic but also subjected to another currentcomponent different in character, and means for controllingthe currentcomponent having the distinguishing characteristic whereby to control agiven operation of the traffic-controlling apparatus, suchtraffic-controlling ap aratus lectively responsive to sue current comonent-to perform such given 0 eration and eing responsive to the otherifl'erent current I component to perform another 0 eration.

44. A railway trafiic control ing system comprising anelectrically-controllable railway traflic-controlling ap aratus locatedon. a railway-line and norma ly in condition to prevent'continuance oftrams along a given track of the railway-line, means for supplying anelectric currentcomponent character ized by a given periodicalternation, a traffic: controlling electric circuit in control of thetrafIic-controlling apparatus and extendmgi therefrom rearward a ong theline of railway' traffic and arranged to conduct the current componenthaving the given eriodic. altereing sef nation but also subjected to t eflow of anratus to control such traffic-controlling ap aratus, suchtrafiic-controlling apparatus eing selectively responsive to suchcurrent component having the given per1od1c alternation to reverse theaforementioned normal condition but being not thus responsive to waytraffic-controlling apparatus located on the other different currentcomponent.

45. A railway trafiic -'controlling system comprising anelectrically-controllable rail- 'way traflic-controlling apparatuslocated on a railway-line, means for supplying an electric currentcomponent characterized bl-yina' trol g given'periodic variation, atraffic-con electric circuit in control of the traffic-com trolling aparatus and extending therefrom rearward a ong the line of railwaytraffic and arranged to conduct the current component having the givenperiodic variation, but also subjected to the flow of another difierentcurrent component, and means for controlling the current having thegiveneriodic variation from a point in rear of t e traflic-controllingapparatus to control such trafiic-controlling apparatus, suchjtrafiic-controllmg apparatus being selectively responsive to suchcurrent having the given periodic variation to perform a giventraffic-controlling operation and being also responsive to the otherdifferent current component to perform another o oration.

46. railway traiific-controlling system comprising anelectrically-controllable railway traflic-controlling ap aratus locatedon a railway-lineand normal in condition to prevent continuance of tramsalong a given track of the railway-line, means for supplying an electriccurrent component characterized by a given periodic alternation, atrafliccontrolling electric circuit in control ofthe trafiic-controllingapparatus and extending therefrom rearward a ong the line of railwaytraffic and arranged to conduct the current component having-the formcurrent component, and means for con nation but also subjects to theflow of a uni:

trolling the current having the given periodic alternationfrom a pointin rear of the traffic- .controlling apparatus to control suchtrafliccontrolling apparatus, such traffic controlling apparatus beingselectivelycontrollable current having the given periodicby 8.110a-ternation to permit continuance of trams ponent. a

along the given railway-track but being not thus responsive to theuniform current com- (gi-ven periodic alter 4-,7L A railway trafiic-controlling system comprising an 'electrically-controllablerailsubjected to the flow of a uniform current component, and means, forcontrolling the current having the given periodic variation from a pointin rear of the traffic-controlling apparatus to control suchtraflic-controlling I apparatus, such traflic-controlling apparatusbeing-selectively responsive to such' current 1 having the givenperiodic variation to perform a given traffic-controlling operation andbeing also responsive to the uniform current component to performanother operation.

48. A. railway traffic-controlling system 'comprisin' anelectrically-controllable traf-' fic-control ing apparatus located on arailway-line, means for supplying an electric cur-' rent componentcharacterized b a periodic variatlon, a rall-circult 1n contro of thetraffic-controllin apparatus and including the traflic-rails o therailway extending in rear thereof and arranged-to conduct the currentcomponent haying the periodic variation but also subjected to flow of anon-periodic current, and means for controlling the currentcomponenthaving the periodic variation by approach of a train toward thetraffic-controlling apparatus from in rear thereof whereby to controlsuch traffic-controlling apparatus, such apparatus being selectivelyresponsive to the current component characterized by the periodicvariation and controllable thereby to erform a given operation and be ring control able by the non-periodic current to perform anotheroperation. In testimony whereof I have aflixed my signature in presenceof two witnesses.

' CLYDE J. COLEMAN.

Witnesses:

HENRY D. WILLIAMS, HERBERT H. Guess.

